Clinical characteristics and outcomes of patients hospitalized with heart failure with preserved ejection fraction and low NT-proBNP levels.

The aim of this study was to investigate the clinical characteristics and prognosis of patients hospitalized with heart failure with preserved ejection fraction (HFpEF) and low N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. Seven hundred ninety consecutive patients hospitalized with HFpEF from 2006 to 2017 were enrolled. Clinical characteristics and outcomes were compared between low NT-proBNP group (<300 ng/L) and elevated NT-proBNP group (≥300 ng/L). 108 HFpEF patients (13.7%) presented with low NT-proBNP levels. Age, body mass index, atrial fibrillation, New York Heart Association functional class, and albumin were independent predictors of low NT-proBNP levels in HFpEF patients. During the median follow-up duration of 1103 days, 11 patients (10.2%) in low NT-proBNP group suffered from primary endpoint event. Elevated NT-proBNP group had a higher risk of all-cause death or heart transplantation than low NT-proBNP group (adjusted HR [95%CI]: 2.36 [1.24,4.49], P = .009). Stratified analyses showed that the association between NT-proBNP (elevated NT-proBNP group vs low NT-proBNP group) and risk of all-cause death or heart transplantation was stronger in non-atrial fibrillation patients than in atrial fibrillation patients (P value for interaction = .025). Furthermore, the associations between NT-proBNP and risk of all-cause death or heart transplantation were stronger in younger and male patients than in older and female patients. However, both subgroups only reached borderline significant (P values for interaction = .062 and .084, respectively). Our findings suggest that low NT-proBNP levels were common in patients hospitalized with HFpEF. Patients with HFpEF and low NT-proBNP levels had a better prognosis than those with elevated NT-proBNP levels, particularly in younger, male, and non-atrial fibrillation patients.

Serum Potassium Levels and Mortality in Hospitalized Heart Failure Patients.

Background: To assess the link between serum potassium ( K + ) and all-cause mortality in hospitalized heart failure (HF) patients. Methods: Hospitalized HF patients (n = 3114) were analyzed at the Fuwai Hospital Heart Failure Center. Before discharge, HF patients were divided into four groups according to the K + level quartiles: K + ≤ 3.96 mmol/L (Q1), 3.96 < K + ≤ 4.22 mmol/L (Q2), 4.22 < K + ≤ 4.52 mmol/L (Q3), and K + > 4.52 mmol/L (Q4). At 90 days, 2 years, and maximal follow-up, all-cause mortality was the primary outcome. Results: Patients with HF in the Q4 group had worse cardiac function, higher N-terminal pro-B-type natriuretic peptide levels, lower left ventricular ejection fractions and lower estimated glomerular filtration rates than patients in the Q2 group. In the multivariate-adjusted Cox analysis, the mortality assessed during the 90-day, 2-year, and maximal follow-up examinations increased in the Q4 group of HF patients but not in the Q1 and Q3 groups. The Q4 group had a 28% (hazard ratio [HR]: 1.28, 95% confidence interval [CI]: 1.09-1.49, p = 0.002) higher risk of all-cause mortality at maximum follow-up. Hypokalemia and hyperkalemia were linked to increased HF mortality risk at the 90-day, 2-year, and maximal follow-up periods. Conclusions: Serum K + levels had a J-shaped association with all-cause mortality in HF patients. Both hypokalemia and a K + level of > 4.52 mmol/L were associated with increased all-cause mortality in the short term and long term, suggesting a narrow target K + range in HF patients. Clinical Trial Registration: Unique Identifier: NCT02664818; URL: clinicaltrials.gov.